Conventionally known as a steering assistance apparatus which assists steering by providing a steering mechanism of a vehicle with a steering torque is one capturing an image in front of the vehicle with a camera, detecting a running path and the position of the vehicle with respect to the running path according to the captured image information, calculating a basic steering assist torque according to the form of the running path, calculating a corrected steering assist torque according to the position of the vehicle, calculating an output steering assist torque according to the basic steering assist torque and corrected steering assist torque, and determining an amount of operation of a steering actuator according to the output steering assist torque as described in Japanese Patent Application Laid-Open No. 2001-10518. This apparatus aims at improving the accuracy of control by controlling the steering by using a form parameter of the running path and a position parameter of the vehicle which are detected with a high accuracy without employing yaw rates.